彬长矿区南部诱发冲击地压覆岩关键层探讨

为分析彬长矿区南部煤矿覆岩关键层的位置，给煤矿冲击地压提治理供技术及理论支撑，采用关键层理论值计算、数值模拟分析以及微震事件验证的综合判定方法探讨了诱发彬长矿区南部煤矿冲击地压的主控层位。经理论值计算，煤层上部200 m覆岩具有三层关键层，从上而下依次是距4#煤层顶板160 m宜君组砾岩坚硬层层、距4#煤层顶板76 m的安定组底界砂岩坚硬层层以及距4#煤层顶板35 m的直罗组底部砂岩坚硬层层。结合数值模拟计算，在起始开挖过程中，煤层顶板约35 m处直落组底界砂岩出现应力集中；随着开挖深度的增加，煤层顶板76 m附近的安定组底界砂岩层逐渐成为水平应力最大部位。综合微震数据的结果，认为煤层顶板35 m处的直落组底界砂岩与煤层顶板76 m处的安定组底界砂岩层均为引起煤矿冲击地压的关键层位，容易产生能量集中，是矿井冲击地压治理的主要目标层位。

Discussion on Key Strata of Induced Rock Burst in Southern Coal Mine of Binchang Mining Area

In order to analyze the position of key overlying strata in the southern coal mine of Binchang mining area and provide technical and theoretical support for the treatment of coal mine rockburst, the main control strata inducing coal mine rockburst in the southern coal mine of Binchang mining area are discussed by using the comprehensive judgment methods of theoretical value calculation of key strata, numerical simulation analysis and microseismic event verification. According to the theoretical value calculation, the overlying 200 m above the coal seam has three key layers, namely, the sandstone layer at the bottom of Zhiluo formation 35 m above the coal seam roof, the sandstone layer at the bottom of Anding formation 76 m above and the gravel layer of Yijun formation 160 m away. Combined with the numerical simulation calculation, during the preliminary excavation of the coal seam, the stress concentration appeared in the sandstone at the bottom of the Zhiluo formation about 35 m away from the coal seam roof; With the increase of excavation depth, the sandstone layer at the bottom of Anding formation near the roof of coal seam about 76 m gradually becomes the position with the maximum horizontal stress. Based on the results of microseismic data, it is considered that the bottom boundary sandstone of Zhiluo formation at 35 m of coal seam roof and the bottom boundary sandstone of Anding formation at 76 m of coal seam roof are the key horizons causing coal mine rockburst, which is easy to produce energy concentration, and is the main target horizon of coal mine rockburst treatment.